21017221512201 has 48 divisors (see below), whose sum is σ = 32533699598400. Its totient is φ = 13550130619200.

The previous prime is 21017221512103. The next prime is 21017221512229. The reversal of 21017221512201 is 10221512271012.

21017221512201 is a `hidden beast` number, since 2 + 101 + 7 + 2 + 21 + 512 + 20 + 1 = 666.

It is not a de Polignac number, because 21017221512201 - 2¹⁴ = 21017221495817 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21017221512241) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8902126 + ... + 11012823.

It is an arithmetic number, because the mean of its divisors is an integer number (677785408300).

Almost surely, 2^{21017221512201} is an apocalyptic number.

It is an amenable number.

21017221512201 is a deficient number, since it is larger than the sum of its proper divisors (11516478086199).

21017221512201 is a wasteful number, since it uses less digits than its factorization.

21017221512201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19915108 (or 19915096 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 27.

Adding to 21017221512201 its reverse (10221512271012), we get a palindrome (31238733783213).

The spelling of 21017221512201 in words is "twenty-one trillion, seventeen billion, two hundred twenty-one million, five hundred twelve thousand, two hundred one".